F0 tornado, Kewanee, Illinois, May 8, 2000

1. F040 to 72 mphthis tornado

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. F173 to 112 mph

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. F2113 to 157 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. F3158 to 206 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. F4207 to 260 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. F5261 to 318 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

F0

Date

May 8, 2000

Touchdown

9:11 PM CDT (02:11 UTC)

Path length

0.1 miles (0.2 km)

Path width

10 yards (9 m)

Deaths

0

Injuries

0

County

Henry County

Touchdown point

41.230, -90.020

Lift-off point

41.230, -90.020

Record number

239

An outflow boundary laid down from morning thunderstorms was located in an east-west fashion near the Illinois and Wisconsin border by early afternoon. The outflow intersected an advancing cold front over East Central Iowa, which enhanced low level convergence. However, the atmosphere remained strongly capped, which allowed for only isolated thunderstorms to develop over Eastern Iowa by mid afternoon. These storms did not generate any reports of severe weather in Eastern Iowa, although they did produce heavy rain, gusty winds and small hail. As the thunderstorms crossed the Mississippi River into West Central Illinois during the evening they intensified. The cap had eroded with the aid of an upper level jet max. The atmosphere was very unstable with Capes of 2500-3500 J/Kg, while deep layer shear from the surface to 6 kilometers was marginal for supercells at 30 to 40 knots. The storms quickly became severe producing large hail and damaging winds in Hancock, Warren and Henry Counties. A weak, short lived tornado was spawned by one of the storms 4 miles west of Kewanee. The tornado touched down in a rural area doing no damage and causing no injuries.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a Slight Risk. The outlook in force was issued at 01:05 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

The Quad Cities radar (KDVN), 63 km away, was scanning. The volume nearest the touchdown began at 02:09 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

The live radar over the trackEvery 2000 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

3 more were confirmed in the United States that day.

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.